Urdenax the Obsessed

{b}{g},{t}, sacrifice a creature: Search your library
for a creature card with the same converted mana
cost and exile it. Create an X/Y abomination
token, where X and Y are the sacrificed creature's
power and toughness. It has all the abilities of the
exiled card, and all the colors of both the
sacrificed card and the exiled card. When the
token leaves the battlefield, shuffle the exiled
card back into your library.
Sanity lost, purpose gained.